[agacera]

Aurora is indeed amazing. However, my experience with it regarding costs is that main cost you have running it is not compute, but IO ($0.2 per million requets [1]).

This cost is kind of hidden since to estimate this in the early stages of a project is an art. In one project on my team the IO cost is about 8x more than cost of instances. But imo it is still worth and I never actually calculated how much we would pay if we were running on RDS + provisioned IOPS.

[phamilton]

It is really hard to estimate because it isn't quite apples to apples. With Aurora we pay for what we use, not what we provision. We used to have some big write spikes for about 5 minutes each hour and so had to massively over-provision IOPS. With Aurora we just pay for the IOPs we use on those spikes.

Right now, on a multiple of the traffic we had before we moved to Aurora we are paying less than half what we used to for IO.